1. Field of the Invention
The present invention relates to a processing chamber that is mainly used as apparatuses for producing semiconductor devices or the like, and it is to be connected to an exhaust system for exhausting the inside of a chamber of such apparatuses.
2. Related Background Art
In the production of semiconductor devices or the like, there are used apparatuses in which an article to be processed (hereinafter, simply referred to as xe2x80x9carticlexe2x80x9d) is placed in a processing chamber, the inside of the processing chamber is exhausted, and a desired processing is carried out therein.
Taking the ashing apparatuses as an example, ashing apparatuses have recently been required to be produced at low cost and to have a high throughput. Therefore, it is necessary to shorten the operation cycle of the chamber in order to reduce the processing time as a factor of the throughput.
A processing chamber used in the ashing apparatus generally has an inner structure of an approximately cylindrical shape, which defines a vacuum vessel capable of being separated into an upper chamber 1 and a lower chamber 2 as shown in FIGS. 4 and 5. Further, the ceiling portion of the upper chamber 1 is provided with a dielectric member 6 such as a quartz plate and a high frequency power supply (not shown), and the lower chamber 2, which is opposite to the upper chamber 1, is provided with a wafer stage 9 having a temperature raising equipment.
When a wafer W as an article is placed on the wafer stage 9, the lower chamber 2 with the wafer stage 9 is moved downward to an wafer exchange (or delivery) position by a considerable distance (designated by an opening distance B in FIG. 5), and the wafer is exchanged by means of a hand 15 of a wafer transferring robot (not shown).
Generally, the operation cycle of the processing chamber comprises the total time of wafer exchanging time, closing time of the lower chamber, vacuum drawing time, plasma-on time, gas introducing time, atmospheric pressure recovering time, and chamber opening time. Therefore, in a case where other units of the ashing apparatus are sufficiently operable within a predetermined time, the throughput of the ashing apparatus depends on the operation cycle of the chamber, especially at the opening and closing time.
Specifically, since the opening and closing time of the lower chamber 2 that is as a factor of the chamber cycle consists of two operations that are both of an opening operation and a closing operation, the operation time thereof has a great influence on the throughput of the apparatus.
However, the operation of the lower chamber 2 has a large operation stroke as described above, so that the operation time thereof will be long. This is attributable to the structure of the chamber. In the prior art chamber, since the side wall of the upper chamber is provided with an introducing port for a processing gas, an introducing port for a purge gas, and an exhaust duct E1 also serving as an exhaust port for drawing a vacuum, the length in the vertical direction is large.
On the other hand, the distance between the upper surface of the wafer stage 9 (i.e., wafer stage surface) of the lower chamber 2 and the dielectric member 6 of the upper chamber 1 needs to be set to an optimum value for fully attaining the processing performance and it is set as small distance as possible in most cases. The structure of the lower chamber satisfying both the conditions is of such a protrusion shape that the wafer stage surface intrudes deeply into the upper chamber from the chamber separation surface by a distance (designated by distance C in FIG. 5) in the closed state, so that the opening distance B for moving the lower chamber to the wafer exchange position will become large.
In FIGS. 4 and 5 reference numeral 3 refers to a microwave introducing part through which microwaves introduced by microwave waveguide MW are introduced. As shown in FIG. 4, body 8 (partly shown) is connected to upper chamber 1. As shown in FIGS. 4 and 5, a seal ring 10 is provided in contact with the lower chamber 2. Lift pin 11, shown in FIGS. 4 and 5, is used to lift the wafer W. Reference numeral 10 refers to a sealing ring, shown in FIGS. 4 and 5. Reference numeral 13 refers to a flange portion, shown in FIGS. 4 and 5.
It is an object of the present invention to provide a processing chamber that can reduce the opening and closing time of the chamber and improve the throughput of the processing without complicating the structure of the chamber and the opening and closing operation.
It is another object of the present invention to provide a processing chamber that can reduce the opening distance of the lower chamber.
According to an aspect of the present invention, there is provided a processing chamber comprising a stage, an upper chamber, a lower chamber which is connectable to and separable from the upper chamber, and an exhaust path, wherein the exhaust path has a separator with an exhaust port which is connectable to and separable from a connector of an exhaust duct, and the separator is configured so as to be able to move along with the lower chamber.
The connector preferably has an elastic member which is extendable in the moving direction of the lower chamber.
The elastic member is preferably a bellows which is capable of extending in the moving direction of the lower chamber.
The elastic member is preferably a rubber for vacuum seal.
The connector preferably has an elastic member which is extendable in the moving direction of the lower chamber and a flange to be in close contact via a sealant with a separation surface of the separator.
The sealant is preferably a seal ring, and the diameter of the seal ring is preferably larger than that of the effective diameter of the bellows.
A separation surface of the lower chamber at a portion for putting an article into and out of the processing chamber is preferably at approximate the same level as an article placing surface of the stage.
A separation surface of the separator is preferably at approximate the same level as an article placing surface of the stage.
A flow path of inside the separator preferably communicates with the lower chamber through an opening formed at a location lower than an article placing surface of the stage.
It is preferable that the separator is separated from the connector of the exhaust duct when separating the upper chamber and the lower chamber from each other and is connected to the connector of the exhaust duct when connecting the upper chamber and the lower chamber to each other.
According to another aspect of the present invention, there is also provided a method of producing a semiconductor device, comprising the steps of:
providing the processing chamber as mentioned above;
providing a wafer; and
placing the wafer in the processing chamber and processing the wafer.
The processing of the wafer preferably comprises the step of ashing a resin provided on the wafer.